Apparatus and Method for the Injection of Viscous Fertilizer Below the Surface of the Soil

ABSTRACT

The invention pertains to apparatus and methods for injecting viscous fertilizer, such as dewatered biosolids, below the surface of the soil. The invention also pertains to apparatus and methods for creating a continuous flow of viscous material and for dividing a flow of viscous material.

1. CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional of application Ser. No. 11/410,811,filed Apr. 24, 2006, the contents of which are incorporated herein inits entirety by reference thereto.

2. FIELD OF THE INVENTION

This invention relates to agricultural equipment. The subject matterinvolves apparatus and methods for injecting viscous fertilizers,including but not limited to dewatered biosolids, semisolid manure, andviscous fertilizers and soil amenders, below the surface of the soil.The subject matter also involves apparatus and methods for creating acontinuous flow of viscous material and for dividing a flow of viscousmaterial.

3. BACKGROUND

Fluid agricultural fertilizers include manure, sewerage and septage andchemical fertilizers with a solids content under about 13 percent byweight. Application of such fluid fertilizers may be done by floodirrigation, aerial spraying, irrigation sprayers, mobile surfacesprayers (tank-type or drag hose type, either of which may incorporatetillers to incorporate the liquid into the soil), and fluid injectors.Fluid injector applicators typically use a shank to loosen and createvoids in the soil so that the liquid fertilizer may be injected into thesoil immediately behind the shank. Gaseous anhydrous ammonia may beinjected in the same fashion. These systems can leave fluid at thesurface if the voids created below the surface are not large enough toaccept the volume of fluid injected.

Fluid agricultural fertilizer application methods have manydisadvantages, both in cost and effectiveness. Flood irrigation, aerialspraying, and irrigation sprayers have significant costs and are limitedby the configuration or topography of the fields. Liquid manure ortreated sewerage fertilizer may produce significant malodors. Mobilesurface spraying and fluid injectors are costly because they requirelarge volumes of liquid to be transported to the application site, andthe volume of fluid to be applied limits the amount of solid nutrientswhich may be applied at one time. Tank surface sprayers cause soilcompaction and high fuel costs due to the weight of the fluidnecessarily carried. Drag hose surface spraying is often impractical onsloped or irregularly-shaped fields. As the solid content of fluidagricultural fertilizer increases, fluid application systems becomeprone to malfunctions and may require special pumps. Fluid systems mayalso require agitation to keep solids in suspension. Mobile sprayingapplications often require tilling to incorporate the fertilizer intothe soil and to reduce malodors. Fluid injection applicators, such asthat described in U.S. Pat. No. 5,865,131 (Dietrich), have beendeveloped to place the liquid below the surface and reduce the need fortilling, but many of the problems of fluid application methods remain:large volumes of fluid to transport, limited amounts of nutrients whichmay be applied at one time, soil compaction, and difficulty acceptinghigher solid content. For treated sewerage, environmental regulationsoften limit where fluids may be applied because of malodors or thepotential for the fluid to migrate to watercourses.

Conventional fluid injection systems are not generally adapted for theinjection of high-pressure fluids. Such systems, with a tubular injectormounted behind a shank, are also not adaptable to the application ofviscous fertilizers, in part because sufficient void space is notmaintained below the surface of the soil to accept the viscousfertilizer, in part because they do not operate at high enough pressure,and in part because the equipment may not be adapted to the solidscontent of viscous fertilizers.

Between about 13-40% solid content by weight, fertilizers, soilamenders, and soil conditioners are viscous, and the term “viscousfertilizer” in this disclosure includes such a range of solid content.However, the apparatus and methods described are effective on a widerrange of materials, and the term “viscous fertilizer” as used in thisdisclosure also refers to fertilizers, soil amenders, and soilconditioners with a solid content falling within a range whose lowerlimit is from 0% to 40% and whose upper limit both is above the lowerlimit and is from 13% to 52%. “Viscous fertilizers” include, but are notlimited to, biosolids, dewatered biosolids, sewage sludge, manure,slurries, or other chemical or mineral fertilizers in the 0-52% solidcontent range.

Viscous fertilizers above about 13% solid content have traditionallybeen applied by manure spreaders that involve an open-topped hopper, aconveying mechanism (e.g, augers, a conveyor belt floor, a live bottomfloor, a walking floor, an apron chain, or a push blade) which conveysthe viscous fertilizer to an open end or side of the hopper whererotating tines fling the material into the air, from which it falls ontothe surface of the ground. A second pass over the application area isoften required to till the material into the soil and to mitigatemalodors. Such viscous fertilizers may also be applied in bulk and thenspread with earthmoving equipment. All these methods may result inuneven application of the viscous fertilizer and repeated and costlyreworking of the soil.

Fertilizers, soil amenders, and soil conditioners with higher solidscontents may be applied as are viscous fertilizers. They may also besupplied in granular or pellet form, in which case they may be appliedwith a centrifugal spreader.

The use of biosolids for fertilization, soil amendment, and/or soilconditioning presents particular problems. At a sewerage treatmentplant, for example, biosolids are found in sewerage at only a fewpercent solid content by weight. However, the cost of transporting thegreat quantities of such fluid required and the difficulties in theagricultural application of such a fluid to the soil generally make itmore efficient to dewater the biosolids before their use in agriculture.

4. SUMMARY

The present invention resolves many of the problems with traditionalagricultural application of fluids and viscous fertilizers by providing,in various aspects and embodiments, apparatus and methods for injectingviscous fertilizer below the surface of the soil. Compared to mobilesurface spraying of fluids, the invention generally requires lessmaterial to be transported to the site of application (i.e., less water)and causes less soil compaction from the weight of a fluid tank. Ascompared to application of fluid fertilizers, the invention generallyallows higher concentrations of nutrients to be applied at one time dueto the higher nutrient concentration of the viscous fertilizer,relaxation of limitations on the amount of fluid fertilizer that can beapplied to the soil at any one time, and broader implementation whilecomplying with nutrient management regulations and clean waterregulations. The invention presents fewer malodor problems because theviscous fertilizer is injected underground and is not sprayed throughthe air and onto the soil surface. The invention permits viscousfertilizer to be applied in places where regulatory and environmentalconcerns would not permit fluid biosolids to be applied due to runoffand malodor concerns. Compared to traditional methods of applying ofsolid and viscous fertilizers, the injection of viscous fertilizer belowthe surface of the soil eliminates the need to make a second pass overthe field to till the material into the soil, and offers advantages withrespect to malodors, uniformity of application, and regulatory andenvironmental concerns.

To permit injection of viscous fertilizer below the surface of the soil,the invention provides for the delivery of viscous fertilizer underpressure to an injection mechanism which places the viscous fertilizerbelow the surface of the soil. The viscous material is pressurized andmovement motivated by a pump, which in some embodiments is a positivedisplacement, rotary lobe pump. The invention further provides for theconveyance of viscous fertilizer to this pump in a continuous manner, soas to allow the injection of viscous fertilizer to be uniform. In someembodiments, a proportioner permits the viscous fertilizer to beproportioned among multiple injectors so as to speed the injectionprocess.

In one embodiment, the invention comprises a trailer-mounted open topcontainer box for receiving and holding the viscous fertilizer. Ahydraulically operated push blade pushes the viscous fertilizer rearwardagainst a third side wall of the container having an outlet. In one suchembodiment, particularly suitable for dewatered biosolids injection, theoutlet is 6 inches high and 9 inches wide. The third side wall usefullyhas facets angled so as to help direct the viscous fertilizer throughthe outlet hole to the pump, which is usefully also mounted on orotherwise carried on the trailer. In this embodiment, the pump ispreferably powered by a power take-off shaft. The pressurized viscousfertilizer exiting the pump in turn enters a proportioner, usefully alsomounted on or otherwise carried on the trailer, which in someembodiments divides the flow; in one embodiment, into 9 divisions. Thestreams are directed into a delivery system comprising flexible hosesand/or pipes adapted to hold pressurized material from each flowdivision. The hoses direct the pressurized viscous fertilizer to aninjection mechanism, which in some embodiments is also mounted on thetrailer and additionally supported by gauge wheels.

In operation of this embodiment, a vehicle, such as a tractor, pulls thetrailer forward. In the injection mechanism, a coulter for each divisioncuts vertically through any stubble into the soil, followed by shankswith sweep points which create voids under the soil. The voids aremaintained under extension plates mounted behind the sweep points.Tubular injectors mounted in the extension plates allow pressurizedviscous fertilizer that enters the tubular injectors to be expelled intothe void, which closes over the injected viscous fertilizer as theinjection mechanism passes. In another embodiment, the coulters may beomitted.

The depth of the injection, preferably 3 to 6 inches below the surfaceof the soil, is adjustable in certain embodiments by adjusting theheight of a strut onto which the gauge wheels are mounted.

For a given pump speed, the speed of the vehicle will determine the rateof viscous fertilizer injection per unit area of soil surface (e.g.,tons per acre). This rate may be further adjusted to accommodate thesolids content of the viscous fertilizer to yield a desired amount ofsolid material injected per unit area of soil surface. For a given pumpspeed and vehicle speed, the push blade speed is typically adjusted tobe slower than a speed that would push the viscous fertilizer fasterthan the pump can accept it (eventually causing the viscous fertilizerto spill out of the top of the box) and faster than a speed that allowsthe pump to accept viscous fertilizer through the outlet hole of thecontainer box faster than the push blade supplies it to the outlet hole(eventually causing the level of viscous fertilizer adjacent to theoutlet hole to fall to the point where air can enter the outlet hole andthe pump, causing uneven injection and possibly causing the pump tostop). Although an adjustable push blade speed is not required, suchadjustment permits a wider range of vehicle speeds to be used inoperation.

5. BRIEF DESCRIPTION OF THE FIGURES

The above and other objects and advantages of the present invention willbe apparent upon consideration of the following detailed description,taken in conjunction with the accompanying drawings, in which likereference characters refer to like parts throughout, and in which:

FIG. 1 is a left side view of an exemplary embodiment of apparatus 100,operably linked to an exemplary leading vehicle 803, for injectingviscous fertilizer 201 below the surface of the soil 101. FIG. 1 furtherdepicts container box 200, pump 400, proportioner 500, delivery system600, and injection mechanism 700.

FIG. 2 is a partial cutaway perspective view of an exemplary embodimentof container box 200, looking from above, in front of and to the leftside of container box 200. For clarity, left wall 203 is omitted, as areportions of this embodiment which are located outside container box 200,and viscous fertilizer 201.

FIG. 3 is a perspective view of a portion of container box 200, pump400, proportioner 500, a portion of delivery system 600, and a portionof injection mechanism 700 of an exemplary embodiment of the apparatus,viewed from the left rear side of the embodiment. Portions of thedelivery system 600 and injection mechanism 700 have been omitted forclarity.

FIG. 4 is a perspective view of injection mechanism 700 of an exemplaryembodiment viewed in a disengaged position (i.e., raised above thesurface of the soil 101) viewed from the left rear side of theembodiment. Some repeated portions of the injection mechanism have beenomitted for clarity.

FIG. 5 is a cross section of a portion of injection mechanism 700 in anengaged position.

FIG. 6 is a partially cutaway view of proportioner 500 without viscousfertilizer inside, viewed from the bottom left side.

FIGS. 7 a through 7 e are views of different embodiments of top plate506 of cylindrical chamber 501 of proportioner 500.

6. DETAILED DESCRIPTION

FIG. 1 depicts an embodiment of apparatus 100 for injecting viscousfertilizer 201 below the surface of the soil 101, operably linked toleading vehicle 803. The embodiment comprises trailer 800. The trailercomprises frame 801 and two left wheels 802 mounted astride the leftside of the frame in tandem and two right wheels similarly mountedastride the right side of the frame. These wheels have balloon tires 810whose relatively large area of contact with the surface of the soil 101minimizes the amount of soil compaction. In operation, trailer 800 isconnected to leading vehicle 803 for towing the apparatus in forwarddirection 804, which is opposite rearward direction 303. In an exemplaryembodiment, leading vehicle 803 is a tractor, but in other embodiments,trailer 800 may be towed by a truck or other vehicle type, or theapparatus may be self-propelled. In still other embodiments, trailer 800may be supported by different arrangements of wheels with differenttires or no tires, or skids.

In still another embodiment, proportioner 500, delivery system 600, andinjection mechanism 700 are mounted on trailer 800 or a self-propelledvehicle, while the container box 200, conveying apparatus 300, and pump400 are not, and the viscous fertilizer moves from the pump to theproportioner through drag hose comprising a length of flexible hosewhich may drag on the ground. Such an embodiment may include one or morebooster pumps between pump 400 and injection mechanism 700.

In yet another embodiment, pump 400, proportioner 500, delivery system600, and injection mechanism 700 are mounted on trailer 800 orself-propelled vehicle, while container box 200 and conveying apparatus300 are not, and viscous fertilizer 201 moves from container box 200 topump 400 through drag hose comprising a length of flexible hose whichmay drag on the ground. Such an embodiment may include one or moreadditional pumps between container box 200 and pump 400.

In a typical embodiment of the present invention, trailer 800 isoperably linked to leading vehicle 803, which vehicle usefully comprisespower take off shaft 806 which provides power pump 400 and hydraulicpump 810 which provides power to hydraulic cylinder 302, proportioner500, and hydraulic cylinder 704. In other embodiments, any componentrequiring power may be powered by another power source, such as ahydraulic pump, a power take off mechanism, an engine, electricity, orothers. In still other embodiments, any such power source may beintegrated with the component requiring the power or may be located onleading vehicle 803, on trailer 800, on a self-propelled vehicle, orelsewhere.

In the embodiment depicted in FIG. 1, power take off shaft 806 isusefully in operable communication with a similar power take off shaft807 on trailer 800, which is in turn connected through a series of gearsand shafts 808 rearward along the longitudinal centerline of trailer800, up to the level of floor 202 of container box 200, transversely tothe outside edge of left side wall 203 of container box 200, rear alongthe outside of left side wall 203 to a point behind third side wall 204of container box 200, and then transversely toward the longitudinalcenterline of trailer 800 where it is in communication with the shaft ofthe pump 400, thus powering pump 400. In other embodiments, the powertake off shaft 807 and gears and shafts 808 may be routed differently topump 400, the source of the power supplied by the power take off may bedifferent, or pump 400 may be powered hydraulically, electrically, ordirectly by an engine.

Leading vehicle 803 may usefully comprise hydraulic pump 810 which isoperably connected via hydraulic hoses 809 to (i) hydraulic cylinder 302operating push blade 301 (shown in FIG. 2), (ii) hydraulic motor 504operating proportioner 500 (shown in FIG. 3), and (iii) hydrauliccylinders 704 operating parallel linkage 703. Usefully, the speed of thehydraulic cylinder 302 is adjustable by the vehicle operator. In otherembodiments, the hydraulic pump may be located elsewhere, such as ontrailer 800 or on a self-propelled vehicle, or any of the items poweredby hydraulics might be powered differently, such as electrically, by apower take off apparatus, or directly by an engine. In otherembodiments, push blade 301 may be driven mechanically, includingchain-driven or by gears.

In some embodiments, container box 200 for containing viscous fertilizer201 is mounted to and above trailer frame 801. Container box 200comprises floor 202, left side wall 203, right side wall 206 (shown inFIG. 2), and third side wall 204. Side wall extensions 205 slope uptoward the front of container box 200 to help prevent viscous fertilizer201 from escaping from the open top of container box 200. In otherembodiments, the interior of container box 200 need not be in the shapeof a parallelepiped, but may be in the shape of a prism, cylinder, or acombination of portions of a prism or cylinder. Third side wall 204 neednot be toward the rear 303 of container box 200, but may instead faceany direction. In other embodiments, container 200 box has a cover butis adapted so that the cover may be opened to permit the introduction ofviscous fertilizer 201 into container box 200. In yet other embodiments,the cover is not so adapted, but another mechanism for introducingviscous fertilizer (such as an inlet port through a side wall or acover, or a partial cover, or mechanism for removal of the push bladefrom the container box) is included to permit the introduction ofviscous fertilizer into container box 200. In still other embodiments,no side wall extensions 205, no third side wall extension 207, and/or nopush blade extension 304 are present.

In still other embodiments, various other mechanisms may be used toconvey viscous fertilizer 201 to pump 400. These may include containersor hoppers which feed pump 400 by gravity or by a combination of gravityand vibration of viscous fertilizer 201, pre-stage pumps, augers, apronchains, or floor 202 comprising a conveyor belt, live bottom, or walkingfloor mechanism.

In a typical embodiment, pump 400 and proportioner 500 are mounted totrailer frame 801 rearward of third side wall 204. Proportioner 500 hasat least one outlet port 507, typically a plurality of outlet ports 507,in some embodiment nine outlet ports 507 (shown in FIG. 6), which are incommunication with pipes 503. Attached to pipes 503 is delivery system600, typically adapted to receive viscous fertilizer 201 from each ofpipes 503. In one embodiment, delivery system 600 comprises ninefittings 601 (shown in FIG. 3), nine flexible hoses 602, and two supportframes 604 to keep hoses 602 from collapsing or kinking. In otherembodiments, the number of outlet ports, pipes, and flexible hoses maybe more or less. In another embodiment, proportioner 500 may be omittedand the flow of pressurized viscous fertilizer leaving pump 400 may bedivided into multiple divisions through one or more branches in piping,flexible hosing, or other conduit between the pump 400 and the injectionmechanism 700. In still another embodiment, proportioner 500 is omittedand pressurized viscous fertilizer 201 is not divided; instead, viscousfertilizer 201 is injected below the surface of the soil at a singlepoint.

Mounted behind and below trailer frame 801 in a typical embodiment isinjection mechanism 700 comprising injector frame 701 oriented roughlyparallel to the surface of the soil and extending in a traversedirection from the longitudinal axis of trailer frame 801. Plow frame701 extends a distance, typically at least one foot, in a transversedirection beyond left trailer tires 802 and beyond the right trailertires. In other embodiments, injector frame 701 may be shapeddifferently and may be of a shorter or longer extent in a traversedirection from the longitudinal axis of trailer frame 801. In stillother embodiments, the injector frame may be omitted and the remainderof the injection mechanism 700 may be mounted to trailer frame 801.

Usefully, an adjustable mounting apparatus, such as parallel linkage703, connects the rear of trailer frame 801 and the front end ofinjector frame 701 such that hydraulic cylinders 704 may be actuated toraise injection mechanism 700, or hydraulic cylinders 704 may bedisengaged allowing injection mechanism 700 to engage the soil. In otherembodiments, the number of hydraulic cylinders may vary. This is usefulto permit apparatus 100 to be moved over surfaces (e.g., roads) withoutdisturbing the surface or damaging injection mechanism 700. In stillother embodiments, an adjustable mounting apparatus may be omitted, oranother type of apparatus for disengaging injection apparatus 700 fromthe surface of the soil (such as a hinging or folding of injector frame701) may be used.

In typical embodiments, at least one, typically two, on occasion more,gauge wheels 702, typically with tires, support injector frame 701 whenhydraulic cylinders 704 is disengaged. In the embodiment depicted inFIG. 1, two gauge wheels 702 are coaxially mounted to strut 717immediately in front of the left side of injector frame 701. Gaugewheels are similarly mounted to the right side of injector frame 701.One or more of the gauge wheels, which may number more or less than thefour described, may also be mounted inboard or outboard of injectorframe 701 and may not be coaxial. Usefully, gauge wheels 702 supportinjector frame 701 and allow adjustment of the vertical distance betweengauge wheels' 702 axle and injector frame 701, thus permittingadjustment of the depth that viscous fertilizer 201 is injected belowthe surface of the soil 101 In other embodiments, injector frame 701 maybe supported by different arrangements of wheels with different tires orno tires, or skids. In yet other embodiments, strut 717 may be omittedfrom the apparatus or the height of injector frame 701 may be adjustablein another fashion, or may not be adjustable. In still otherembodiments, the depth that viscous fertilizer 201 is injected below thesurface of the soil 101 may not be adjustable or may be adjustable byvarying mounting apparatus 703.

FIG. 2 depicts the interior of container box 200 of a typical embodimentof the apparatus, and the operation of conveying apparatus 300. In thisembodiment, container box 200 holds viscous fertilizer 201 (omitted fromFIG. 2) and comprises floor 202 mounted on trailer frame 801, left sidewall 203 (partially omitted from FIG. 2), right side wall 206, thirdside wall 204, side wall extensions 205 (partially omitted from FIG. 2),and third side wall extension 207. This embodiment has no fourthsidewall, but merely panel 208 at the forward end of the left and rightside walls 203, 206. In this embodiment, push blade 301 and push bladeextension 304 serve to keep viscous fertilizer 201 from escaping theforward side of container box 200.

In this exemplary embodiment, conveying apparatus 300 comprises pushblade 301 above which is mounted push blade extension 304. Push bladeextension 304 is inclined in a rearward direction 303 to help preventviscous fertilizer 201 from overtopping the push blade. Hydrauliccylinder 302 is powered by and connected to vehicle-mounted hydraulicpump 810 via hydraulic hoses 809 (shown in FIG. 1). In operation, pushblade 301 is moved by hydraulic cylinder 302 in a rearward direction 303(opposite of forward direction 804), thereby pushing the viscousfertilizer toward third side wall 204. The vertical movement of pushblade 301 is usefully constrained in some embodiments by shoe 305 whichis connected to the push blade and which is slidably fitted to the webof I beam 306 mounted to floor 202, so that the top flange of I beam 306constrains shoe 305 and the push blade 301 from rising off the floor,but does not constrain forward 804 and rearward 303 movement of pushblade 301. The lateral movement of push blade 301 is constrained by leftand right side walls 203, 206. An optional rubber flange on the sidesand bottom of push blade 301 prevents at least some viscous fertilizer201 from passing to the forward side 804 of push blade 301. In anotherembodiment, the vertical movement of push blade 301 is constrained byguides along side walls 203, 206 or by a cover over container box 200.

Third side wall 204 of container box 200 has, in the illustratedembodiment, extension 207 along its top edge and rectangular outlet hole307 centered along the bottom edge of third side wall 204. In otherembodiments, outlet hole 307 may be of other shapes and orientations.The plane of the entrance to outlet hole 307 is offset behind thesurface defined by the rearmost edges of side walls 203, 206 and floor202. Third side wall 204 has facets 209, 210, 211 (also illustrated inFIG. 3) which accommodate the offset. Facet 209 is inclined from thevertical to slope down and rearward 303 from the top edge of rear wall204 to the top of outlet hole 304. The other facets 210, 211 arevertical but slanted from the rear edge of right and left side walls,respectively 206, 203, to the right and left edges of outlet hole 307.The intersection of these facets define inclined, diagonal, obtusecorners 213. Floor extension 212 is coplanar with floor 202 and extendsbehind floor 202 to the bottom of outlet hole 307. Through this floorextension is an optional circular clean-out hole 213 which is closedduring operation of apparatus 100 but which may be opened to allowaccess. In another embodiment, third side wall 204 may be conicallyshaped rather than faceted, or may be comprise facets and curvedsurfaces. The location of outlet hole 307 within the third side wall maybe varied, or it may be located in the floor 202, floor extension 207,or it may span several surfaces that make up container box 200.

As viscous fertilizer 201 is pushed rearward in operation by push blade301, the facets 209, 210, 211 of third side wall 204 direct viscousfertilizer 201 toward outlet hole 307 in third side wall 204 which isconnected to pump 400.

Above outlet hole 307 in this embodiment, baffle 308 is attached tothird side wall 204 about one-third of the distance from floor extension202 to the top of third side wall 204. When hydraulic cylinder 302 isoperated so slowly as to move less viscous fertilizer 201 toward outlethole 307 than pump 400 draws out of container box 200 through outlethole 307, a hole may form in the surface of viscous fertilizer 201adjacent to third side wall 204. If this situation continues, the holemay deepen and eventually reach outlet hole 307, thereby disrupting thecontinuous flow of viscous fertilizer to pump 400 and thereafter belowthe surface of the soil. Baffle 308 usefully delays the onset of thisadverse operational condition by allowing the pump to draw viscousfertilizer into outlet hole 307 from an area of container box 200 whichis not adjacent to third side wall 204. In other embodiments, the bafflemay be omitted. In still other embodiments, floor extension 212 may beextended laterally so as to increase the degree of inclination from thevertical of center facet 209, or may not coplanar with the floor 202.Excessive of inclination of center facet 209 may result in a largevolume of viscous fertilizer 201 that cannot be removed from containerbox 200 through use of conveying apparatus 300.

In another embodiment, outlet hole 307 is located in floor extension 212with pump 400 moved to accommodate the position of outlet hole 307 or aconduit added to carry viscous fertilizer 201 from outlet hole 307 topump 400.

FIG. 3 depicts the rear of container box 200, pump 400, and proportioner500 of a typical embodiment. In this embodiment, third wall 204 iscomprised of three facets, 209, 210, 211, forming corners 213, and topextension 207. Pump 400 is mounted on platform 401 attached to trailerframe 801. The pump inlet located on the forward side of pump 400 isconnected to the rear of outlet hole 307 (shown in FIG. 2). The pump ispowered by power take off shaft 806 of vehicle 803 (shown in FIG. 1)which is transmitted to the pump through power take off shaft 807 andgears and shafts 808. Pump 400 is usefully a positive displacement,rotary lobe pump, VL series manufactured by Jurop, Inc. In otherembodiments, the pump may be of another types, including but not limitedto positive displacement pumps such as piston or ram pumps.

Pump 400 is typically capable of pumping viscous fertilizer 201 at apressure of at least 40 p.s.i. In operation of the embodiment depictedin FIG. 1 with viscous fertilizer 201 consisting of dewatered biosolidswith 30% solid content by weight, pressures may vary from 100 to 130p.s.i. at conduit 402 (shown in FIG. 3). The preferred pressuregenerally increases with the viscosity or solid content of viscousfertilizer 201. The preferred pressure also depends upon the number ofinjectors 711 (shown in FIG. 4), the size and pressure capacity ofdelivery system 600, and the configuration of proportioner 500.

With further reference to the embodiment illustrated in FIG. 3, from theoutlet at the rearward side 303 of pump 400, pressurized viscousfertilizer 201 enters conduit 402, which is in this embodiment ofrectangular cross section approximately 6 inches by 9 inches. The crosssectional size and shape of conduit 402 may be changed depending uponthe capacity and position of pump 400 and proportioner 500. Conduit 402leads rearward and curves up vertically to enter proportioner 500. Inanother embodiment, proportioner 500 is located immediately adjacent topump 400 such that conduit 402 is unnecessary.

Referring to the particular embodiment depicted in FIG. 6, propotioner500 comprises chamber 501 comprising a top plate 506, a bottom plate505, and a cylindrical wall 514, which is supported by struts 502attached to trailer frame 801 (shown in FIG. 3). An opening throughbottom plate 505 is in communication with conduit 402. An optional wearplate 517 shaped as an annulus is mounted upon the bottom face of topplate 506. Through top plate 506 and wear plate 517 are nine outletports 507 which are in communication with nine pipes 503 which leadvertically up and curve over horizontally. Outlet ports 507 aredistributed axisymmetrically about top plate 506 and wear plate 517.Outlet ports 507 are, in this embodiment, teardrop shaped with sigmoidalbars 508 across their centers. Motor 504 is mounted above chamber 501and is in communication with shaft 509, which is coaxial with chamber501 and which passes through top plate 506 so as to prevent the escapeof viscous fertilizer from the interior of chamber 501. Motor 504 turnsshaft 509 in a counterclockwise direction 516 viewed from the top. Sixaxisymmetrical horizontal arms 510 are rigidly attached to shaft 509within chamber 501 by a bolt 518 coaxially threaded into the bottom ofshaft 509 and by a locking bar 519 whose ends are bolted into arms 510so as to prevent bolt 518 from unscrewing when shaft 509 rotates. Inother embodiments, other methods well known in the art may be used toattach arms 510 to shaft 509. Rod 511 is slidably fitted into a verticalhole near the outside end of arm 510 such that rod 511 may slidevertically. Puck 512 is mounted atop rod 511. Puck 512 is a squatcylinder with a planar top surface oriented parallel to the bottom faceof wear plate 517. Compression coil spring 513 mounted on rod 511 biasesthe top surface of puck 512 flat against wear plate 517. Scraper 515 maybe optionally mounted to arm 510 such that, when shaft 509 turns indirection 516, the top edge of scraper 515 precedes puck 512 across wearplate 517 over each outlet port 507.

In other embodiments of proportioner 500, chamber 501 may have otherorientations. Wall 514 and may be in the shape of a prism, or acombination of portions of a prism or cylinder. Shaft 509 may turn inthe other direction. The number of outlet ports 507 with correspondingpipes 503 may be more or less. Similarly, the number of arms 510, rods511, pucks 512, and springs 513 may be more or less. In anotherembodiment, pipes 503 may be of a different shape or eliminated suchthat delivery system 600 is connected directly to cylindrical chamber501.

In operation of the embodiment shown in FIG. 6, viscous fertilizer 201is introduced into chamber 501 through conduit 402 under pressure.Hydraulic motor 504 is connected to hydraulic hoses 809 from thehydraulic pump 810 on the vehicle 803 (shown in FIG. 1). In otherembodiments, motor 504 may be powered differently, such as by a powertake off shaft, an engine, or electrically. Motor 504 rotates shaft 509,arm 510, rod 511, puck 512, spring 513, scraper 515, bolt 518, andlocking bar 519 (together, the “rotating parts”) in direction 516 at aspeed of approximately 380 revolutions per minute. As puck 512 rotates,it alternately exposes and covers portions of outlet port 507 such thatthe flow of viscous fertilizer 201 out of chamber 501 through eachoutlet port 507 is alternately allowed and restricted. By periodicallyrestricting the flow from each outlet port 507, either completely orsubstantially, proportioner 500 substantially reduces any variation influx through each outlet port 507 which might occur due to the geometryof the proportioner, variations in the viscosity of viscous fertilizer201, gravity, variation in the length of and friction associated withthe components of the delivery system 600 for each outlet port 507, etc.

In other embodiments of proportioner 500, bias may be applied to puck512 through a torsion or planar spring. In yet other embodiments, arm510 may be hinged to the shaft 509, and the bias may be applied to theentire arm. In yet other embodiments, the rotating parts may be replacedwith a rotating disk which lies flat against the bottom surface of wearplate 517. This disk has solid areas and open areas (such as holes)which alternately cover and expose portions of each outlet port 507 asthe disk spins, in the same manner as pucks 512 in the embodiment shownin FIG. 6.

Proportioner 500 additionally serves as a macerator and apparatus tobreak up solid clumps within viscous fertilizer 201 and to prevent solidclumps from clogging delivery system 600 and injector mechanism 700.This is accomplished in three ways. First, the vertical orientation ofproportioner 500, with top plate 506 above bottom plate 505 and walls504 oriented vertically, allows relatively dense contaminants in viscousfertilizer 201, such as rocks or pieces of metal, to collect on bottomplate 505 rather than pass out through the outlet ports 507. A clean-outhole 517 (shown in FIG. 3) is provided. Second, the spinning of therotating parts tends to mix viscous fertilizer 201 to make sure anyclumps within are fully wetted and macerated. Third, the bias of pucks512 against wear plate 517 and their motion across outlet ports 507serves to shear off any clumps that may remain in viscous fertilizer201. In this respect, the teardrop shape of outlet ports 507 with theconverging sides of the teardrop oriented in direction of rotation 516tends to hold any clumps in place so that that shearing force of puck512 may be applied. In addition, sigmoidal bars 508 create two sets ofconverging sides with which puck 512 may interact to shear clumps.Optional Scrapers 515 serve much the same purpose but may protect pucks512 from damage which might otherwise affect the pucks' ability to sealoutlet ports 507. However, the maceration and anti-clogging functions ofproportioner 500 may be omitted from other embodiments, which may haveoutlet ports 507 of any shape, may omit sigmoidal bars 508, may omitslidably fitted rods 511 and springs 513, may omit scrapers 515, or mayhave other orientations.

The pressure of viscous fertilizer 201 maintained in proportioningsystem 600 is, in part, dependent upon the relative cross sectional areaof conduit 402 and the sum of the cross sectional areas of all outletports 507 minus the amount of those areas covered by pucks 512. Thus, tomaintain a desired pressure of viscous fertilizer 201 which mayfacilitate its movement through proportioning system 600, differentembodiments may vary the number of outlet ports 507 or vary the numberof pucks 512 (with corresponding different numbers of arms 510, bars511, springs 513, and scrapers 515). One such embodiment, reflected inthe embodiment in FIGS. 1-6 and 7 e, uses viscous fertilizer 201comprising dewatered biosolids with 30% solids content, approximately100-130 p.s.i. pressure in conduit 402, a cross sectional area ofconduit 402 of about 54 square inches (6 inches by 9 inches), six arms510 and pucks 512, and an exposed cross sectional area of the exposedoutlet ports 507 of approximately 30 to 33 square inches (nine ports ofabout 7 square inches each, about half of which area is blocked at anyone time).

It is preferred that the pressure in proportioning system 600 remainnearly constant in order that the rate of injection of viscousfertilizer below the surface of the soil remain constant, and thus theamount of nutrients injected per acre be uniform. Some variation inpressure is sometimes desirable, however, as it may help clear anypotential any clogs that may form in proportioning system 600. Tomaintain a constant pressure, it is desirable that the total crosssectional area of outlet ports 507 exposed (that is, not covered bypucks 512) remain nearly constant throughout the entire rotation of therotating parts relative to the outlet ports. In the exemplary embodimentillustrated in FIG. 7 a, this is accomplished by four circular outletports 507 arranged axisymmetrically through top plate 506 and with puck512 shaped as the portion of an annulus subtending a 90 degree angle,such that as the puck rotates about the axis of shaft 509 in direction516, the trailing edge of puck 512 begins to expose one outlet port justas the leading edge of puck 512 begins to cover the adjacent outletport. In this embodiment, the sum of areas of outlet ports 507 which areuncovered equals the area of three outlet ports, regardless of wherepuck 512 is in its rotation about shaft 509. Outlet ports 507 need notbe circles, but can be of any shape, and the number of ports and pucksmay vary. In the exemplary embodiment illustrated in FIG. 7 b, forexample, four star-shaped outlet ports and two pucks are present. Inthis embodiment, the area of two stars is left uncovered at all timesduring the rotation of the pucks. Where outlet ports 507 are notcircular, pipes 503 may have a cross section that conforms to the shapeof outlet ports 507, may remain circular and circumscribe outlet ports507, or may be belled out so as to cover outlet ports 507 but have acircular cross section through most of their length, as show in FIG. 3.Pipes 503 need not remain of constant cross section, but may vary so as,for example, to become of circular cross section where fitting 601(Shown in FIG. 3) occurs. In the exemplary embodiment illustrated inFIG. 7 c, outlet ports 507 subtend angles with respect to shaft 509which are greater than 360 degrees divided by the number of outlet ports(here, 90 degrees), and thus outlet ports 507 radially overlap oneanother. In the exemplary embodiment illustrated in FIG. 7 d, puck 512is not shaped as a portion of an annulus, and the total area of outletports 507 not covered by puck 512 may vary, slightly, as puck 512rotates about shaft 509.

In yet other embodiments, the number of outlet ports 507 may be eithermore or less, and the number of pucks 512 may be greater than one. InFIG. 7 e, nine outlet ports 507 are arranged axisymmetrically throughtop plate 506 about shaft 509. Each outlet port 507 has teardrop shapewhich subtends an angle with respect to shaft 509 which is greater than40 degrees (i.e., 360 degrees divided by 9) and which overlaps theadjacent outlet port. Three circular pucks 512 each subtend an angle ofslightly greater than 40 degrees

The radial extent of puck 512 is greater than the radial extent ofoutlet port 507 such that puck 512 has both a radially inner portion anda radially outer portion in contact with the bottom face of wear plate517 throughout the entire rotation of the rotating parts relative to topplate 506 and wear plate 517. This permits a greater bias pressure to beapplied to each puck 512 by spring 513 without puck 512 catching on thelip of outlet port 507. Bar 508, whose bottom surface is coplanar withthe bottom face of wear plate 517, also helps serve the same function.

Referring again to FIG. 3, delivery system 600 comprises fitting 601 oneach of nine pipes 503 which seals each pipe 503 to the upper end offlexible hose 602 for delivering the pressurized viscous fertilizer 201to injection mechanism 700. The lower ends of delivery hoses 602 aresimilarly connected to tubular injector 711 by another fitting 603(shown in FIG. 4). Fittings 601, 603 permit hoses 602 to be removed frompipes 503 and tubular injectors 711 for cleaning. Flexible hoses 602 aresupported from collapsing or kinking by support tray 604 which isattached to injector frame 701. In other embodiments, the deliverysystem may comprise piping without hose, hosing without pipes, with orwithout support tray 604. In still other embodiments, another type ofconduit, such as a channel, may be substituted for some or all of pipes503 or flexible hoses 602 or both.

Usefully, injection mechanism 700, may be disengaged from the surface ofthe soil 101 by hydraulic cylinder 704. When actuated, cylinder 704raises parallel linkage 703 which connects injector frame 701 to trailerframe 801. Hydraulic cylinder 704 is powered by hydraulic pump 810 onvehicle 803 (shown in FIG. 1) via hydraulic hoses 809. In otherembodiments, injection apparatus 700 may be moved by a differentmechanical connection well known in the art. Parallel linkage 703 oranother mechanical connection may be powered by a hydraulic cylinder 704or by a manual crank, an engine, a power take off apparatus, orelectrically.

FIG. 4 depicts injection mechanism 700 of the illustrated embodimentviewed in a disengaged position (i.e., raised above the surface of thesoil 101), as viewed from the left rear side of the embodiment. Plowframe 701 is mounted onto trailer frame 801 by parallel linkage 703,shown in FIG. 3.

In the embodiment illustrated, a series of nine coulters 705 are mountedonto injector frame 701, arranged parallel to forward direction 804 andarranged to cut through any stubble into the surface of the soil 101when apparatus 100 is moved in the forward direction 804. Coulters 705are mounted in two rows alternating front and rear, with hinges andsprings 706 biased such that when coulter 705 hits a large rock orsimilar obstruction, it is deflected backwards, and then sprung backinto position when the obstruction is passed. In another embodiment,coulter 705 is held in position by shear fittings, or rigidly attachedto injector frame 701. Coulters 705, springs 706, and their arrangementand operation are well known in the art. In another embodiment, thecoulters and springs are omitted. In another embodiment, the relativelocation of the coulters is changed to a single row, a chevron, oranother arrangement.

Also mounted onto injector frame 701 in this embodiment are a series ofnine shanks 707 with hinges and springs 716 arranged to follow coulters705 when apparatus 100 is moved in forward direction 804. The embodimentin FIG. 4 shows C-tine shanks, but in other embodiments, S-tine shanks,straight-tine shanks, or other types of shanks well known in the art maybe used. Hinges and springs 716 are biased such that when shank 707 hitsa large rock or similar obstruction, it is deflected in a rearwarddirection 303 and then sprung back into position when the obstruction ispassed. In another embodiment, shanks 707 are held in position by shearfittings, or rigidly attached to injector frame 701. Shanks 707, hingesand springs 716, and their arrangement and operation are well known inthe art. Sweep point 708 is mounted onto the lower end of each shank 707with bolts 709 (shown in FIG. 5). Shanks 707, springs 716, sweep points708, bolts 709, and their arrangement are well known in the art.

Behind each sweep point 708, in typical embodiments, is extension plate710 which is oriented parallel to the surface of the soil 101. Throughthe extension plate is a hole to which tubular injector 711 is butted.Tubular injector 711 extends from extension plate 710 upward to fitting603 which attaches the top of injector 711 to the flexible hose 602.Each tubular injector 711 is rigidly attached to its corresponding shank707 by bracket 712 and U-bolt 713. Each extension plate 710 ispositioned against shank 707 by flange 714 attached to extension plate710 and by bolts 709. Tab 715 at the rear of extension plate 710 isinclined downward and rearward. In other embodiments, tubular injector711 and/or extension plate 710 may be fitted and attached to the shankin another manner, including welding, riveting, bolting, and/or withinterlocking flanges. In yet other embodiments, a separate extensionplate 710 may be omitted an sweep point 708 may extend in a rearwarddirection 303 to a point behind injector 711.

FIG. 5 is a cross section of a portion of injection mechanism 700 of anexemplary embodiment in operation. As leading vehicle 803 pullsapparatus 100 (shown in FIG. 1) in forward direction 804, coulters 705cut through any stubble into the surface of the soil ahead of shanks707. Sweep points 708 form voids 716 below the surface of the soil 101which is maintained to the rear 303 of sweep points 708 by extensionplate 710. Pressurized viscous fertilizer 201 enters tubular injector711 and is injected into void 716 under extension plate 710. Asinjection mechanism 700 passes, tabs 715 limit the thickness of theviscous fertilizer left below the surface of the soil 101 and encouragesviscous fertilizer 201 to spread transversely across void 716. In otherembodiments, injectors 711 may extend through extension plate 710 intovoid 716. In other embodiments, the lower (nozzle) ends of injectors 711may have a different shape, such as a fan shape oriented transverse tothe forward direction 804, to enable viscous fertilizer 201 to befurther spread transversely across void 716.

In other embodiments, a different point shape may be used, including butnot limited to narrower sweep points 708, chisel points, or knifepoints, and/or the width of extension plate 710 may be narrowed, suchthat operation of apparatus 100 results in less tilling of the soilsurface; however, these embodiments generally result in smaller voids716 which may limit the amount of viscous fertilizer 201 that may beinjected below the surface of the soil 101. In another embodiment, achisel point may be used and extension plate 710 eliminated, such thatinjector 711 is mounted to shank 707 such that the lower end of injector711 terminates below the surface of the soil 101 behind shank 707, inwhich case viscous fertilizer 201 would be injected in a vertical slitcut by the chisel point and shank 707, the depth of which depends inpart upon the relative vertical position of the lower end of injector711 to the lower end of shank 707 and the chisel point.

All publications, patents, patent applications and other documents citedin this application are hereby incorporated by reference in theirentireties for all purposes to the same extent as if each individualpublication, patent, patent application or other document wereindividually indicated to be incorporated by reference for all purposes.

While various specific embodiments have been illustrated and described,it will be appreciated that various changes can be made withoutdeparting from the spirit and scope of the invention(s).

1. A method for injecting viscous fertilizer below the surface of thesoil comprising: (a) providing a means for containing viscousfertilizer; (b) providing a means for conveying said viscous fertilizerfrom said containing means; (c) providing a pumping means for receivingsaid viscous fertilizer from said containing means via said conveyingmeans and for displacing said viscous fertilizer under pressure; (d)providing a proportioning means for receiving said viscous fertilizerfrom said pumping means under pressure and distributing said viscousfertilizer into at least one outlet port under pressure; (e) providing adelivery means for moving said viscous fertilizer from said outlet portsunder pressure; and (f) providing a injection means for receiving saidviscous fertilizer from said delivery means and injecting said viscousfertilizer below the surface of the soil as said injection means ismoved in a forward direction. (g) placing said viscous fertilizer insaid containing means; (h) activating said conveying means, pumpingmeans, and proportioning means; and (i) moving said injection means in aforward direction along the surface of the soil; wherein said viscousfertilizer is injected below the surface of the soil.
 2. A method forcreating a pressurized stream of viscous fertilizer comprising: (a)providing an upwardly open container box with at least a first, second,and third side wall, said third side wall having an outlet hole throughwhich said viscous fertilizer may pass outside said container box; (b)providing a push blade disposed so as to prevent said viscous fertilizerfrom escaping said apparatus from the side of said container boxopposite said third side wall; (c) providing a means capable of movingsaid push blade at least partially within said container box toward saidthird side wall; (d) providing a pump whose inlet is in communicationwith said outlet hole; (d) placing said viscous fertilizer in saidcontainer box; and (h) activating said means and said pump; wherein saidpush blade moves at least partially within said container box towardsaid third side wall to effect exit of contained viscous fertilizerthrough said outlet hole and into said pump, wherein said viscousfertilizer exits said pump in a pressurized stream.
 3. An method fordividing a flow of viscous material comprising: (a) providing acylindrical chamber with first and second ends for holding viscousmaterial under pressure; (b) providing an inlet port through said firstend; (c) providing a shaft extending through said second end coaxiallywith said cylindrical chamber; (d) providing a motor capable of rotatingsaid shaft; (e) providing a plurality of outlet ports opening throughsaid second end axisymmetrically with respect to said shaft; (f)providing at least one rotatable radial arm disposed inside of saidchamber and attached to said shaft; (g) providing at least one puckconnected to said arm wherein one face of said puck is parallel to andin contact with said second end, and wherein at any angle of rotation ofsaid shaft, said puck covers a fraction of the total area of said outletports, and wherein at any two angles of rotation of said shaft, saidfractions do not differ by more than 20% of the larger; (h) introducingsaid viscous material into said inlet port under pressure; and (i)activating said motor such that it rotates said shaft; wherein saidviscous material is expelled in from said outlet ports.
 4. An method fordividing a flow of viscous material comprising: (a) providing acylindrical chamber with first and second ends for holding said viscousmaterial under pressure; (b) providing an inlet port through said firstend; (c) providing a shaft extending through said second end coaxiallywith said cylindrical chamber; (d) providing a motor capable of rotatingsaid shaft; (e) providing a plurality of outlet ports opening throughsaid second end axisymmetrically with respect to said shaft; (f)providing a rotatable disk disposed inside of said chamber and coaxiallyattached to said shaft, such that one face of said disk is parallel toand in contact with said second end; and (g) providing at least onehole, opening, or notch in said disk, wherein at any angle of rotationof said shaft, said disk does not cover a fraction of the total area ofsaid outlet ports, and wherein at any two angles of rotation of saidshaft, said fractions do not differ by more than 10% of the larger; (h)introducing said viscous material into said inlet port under pressure;and (i) activating said motor such that it rotates said shaft; whereinsaid viscous material is expelled in from said outlet ports.
 5. A methodof for injecting pressurized viscous fertilizer below the surface of thesoil comprising: (a) providing a injector frame; (b) providing at leastone shank attached to said injector frame, each such shank disposed soas to be drawn through the soil when said injector frame is moved in aforward direction; (c) providing a plate disposed behind each of saidshanks and oriented parallel to the surface of the soil so as tomaintain voids beneath the surface of the soil behind said shanks andbeneath at least part of said plate when said injection means is movedin said forward direction; (d) providing a tubular injector having a topend and a nozzle end disposed behind each of said shanks; (e)introducing pressurized viscous fertilizer into said top end of saidtubular injectors; (f) moving said injector frame in said forwarddirection; wherein when said viscous fertilizer is introduced underpressure into said top ends of said injectors, it is expelled into saidvoids through said nozzle ends of said injectors.